Container and method for packaging material sensitive to contaminants

ABSTRACT

A packaging method is disclosed using a container having an integral body member forming top, bottom and side walls, two end walls having flaps on all sides, and a plastic film shrink-fit around the container.

United States Patent [1 1 Cothran et al.

[ Jan. 16, 1973 [54] CONTAINER AND METHOD FOR PACKAGING MATERIAL SENSITIVE TO CONTAMINANTS [75] Inventors: Samuel Bynum Cothran; James Rodney Kirk, both of Florence, SC.

[73] Assignee: E. I. du Pont de Nemours and Company, Wilmington, Del.

22 Filed: Aug. 3, 1970 21 Appl. No.: 60,423

[52] U.S. Cl. ..S3/27, 53/30, 206/58 [51] Int. Cl. ..B65b 53/02 [58] Field of Search ..53/30, 194, 33, 27; 206/58,

206/65 S, 78 BA; 229/37, 48, 87 R [56] References Cited UNITED STATES PATENTS 3,338,399 8/1967 Burt ..206/58 3,331,105 7/1967 Gordon ..229/D1G. 12 3,134,525 5/1964 Holcombe ..206/58 X 3,454,155 7/1969 Voissem et al. 206/58 3,572,575 3/1971 Dorofachuk ..229/37 E X 3,259,298 7/1966 Gorton ..206/45.33 X

Primary Examiner-Robert C. Riordon Assistant Examiner-Eugene F. Desmond Attorney-Francis A. Paintin 5 7 ABSTRACT A packaging method is disclosed using a container having an integral body member forming top, bottom and side walls, two end walls having flaps on all sides, and a plastic film shrink-fit around the container.

6 Claims, 6 Drawing Figures PATENTEDJAH 16 I975 3.710.539

sum 1 OF 2 INVENTORS SAMUEL BYNUM COTHRAN JAMES RODNEY KIRK 'Cy/AWQL,

ATTORNEY PATENTEDJAH 16 ms 3.710.539

SHEE] 2 [1F 2 INVENTORS SAMUEL BYNUM COTHRAN JAMES RODNEY KIRK ATTORNEY CONTAINER AND METHOD FOR PACKAGING MATERIAL SENSITIVE TO CONTAMINANTS BACKGROUND OF THE INVENTION This invention relates to the packaging of material sensitive to contaminants and, more particularly, to a container therefor.

Many materials which are sensitive to contaminants, e.g., polyethylene terephthalate film destined for use as a base film for magnetic tape, present difficult problems in packaging the material for shipment. Not only must great care be taken to protect the material from damage due to impact, but also the container must present an effective barrier to contaminants from the outside. But merely having these measures of protection is not enough. If the container is sealed by fastening the flaps thereof in place with means such as staples or glue, merely opening the container will generate sufficient dust and particulate matter to contaminate the materials stored within the container. It is also highly desirable to avoid any method of packaging the material which involves the need for maneuvering it during the packaging operation; such methods involve the possibility of damage to roll surfaces.

Another problem encountered by a commercial film manufacturing facility is the need for a large number of containers of different lengths to accommodate the wide variety of film lengths sold. If one tries to reduce the number of different container lengths, it results in using a longer container than required in many cases which must be filled with stuffing material between the roll ends and the end walls. Such stuffing material is a prime source of contamination internal to the con tainer.

Finally, it is desirable to provide a container which on opening will present the material stored therein in a free-standing position without the need for maneuvering to remove it from the container.

DETAILED DESCRIPTION OF THE INVENTION The packaging of materials sensitive to contaminants can be improved in accordance with the instant invention which is particularly pointed out in the appended claims and is illustrated, in its preferred embodiments, in the accompanying drawings wherein:

FIG. 1 is a perspective view of the elements which make up the container of this invention;

FIG. 2 is the same perspective view of the elements described in FIG. 1 illustrating how a roll of material fits therein;

FIG. 3 illustrates the container of the invention covered with two sleeves of heat-shrinkable plastic film;

FIG. 4 illustrates the container of the invention after the film has been shrink-fitted around the container;

FIG. 5 illustrates the container of the invention covered with a single sleeve of heat-shrinkable plastic film of extended length; and

FIG. 6 illustrates the container of FIG. 5 after the film has been shrink-fitted around the container.

Referring now to the drawings, a container body member 10 is made up of bottom wall 11, side walls 12 and 13 and two portions of the top wall 14 and 15. All the walls and portions thereof 11 through 15 are integral with the body member 10 which is preferably formed of a material such as corrugated Kraft board sheet. The boundaries, e.g., 16, between the walls such as bottom wall 11 and side wall 12 are formed by creasing the sheet material. This is preferably done in such a way that the crease retains some resilience so that the body member 10 tends to spring open as illustrated in FIGS. 1 and 2 when not restrained. End wall members 17 and 18 each have four inwardly directed flaps arranged along their peripheries: end wall member 17 has top flap 19, bottom flap 20 and two side flaps 21 and 22; and end wall member 18 has top flap 23, bottom flap 24 and two side flaps 25 and 26. Again, it is preferred that the creases which form the boundaries between the end wall members and their flaps be resilient. It may be desirable to fasten flaps 20 and 24 to the interior side of bottom wall 11 along the respective ends thereof, since in opening the container as will be described hereinafter it will not be necessary to remove those flaps from their fastened position on bottom wall 11; staples or adhesives can be used without the problems discussed hereinabove. If desired, the same result as fastening of the end wall flaps 20 and 24 to the bottom wall 11 can be accomplished by cutting the body member 10 and both end walls 17 and 18 from a single sheet of corrugated board making all walls integral.

A roll of plastic film material 30 wound on a concentric core (not shown) is supported between the pair of end-suspension support panels 31 and 32. Suitable means of suspension is accomplished by the insertion of.

a flanged plug (not shown) through a central opening in each of panels 31 and 32. The plug also engages the interior of the concentric roll core (not shown). Such means of suspension are well known to those skilled in the art. A particularly suitable end-suspension support panel for use in connection with this invention is that shown and described in assignees copending US. patent application of S. B. Cothran and C. A. Henry, Ser. No. 60,422, filed concurrently herewith.

To assemble the container, the body member 10 can be formed into walls 11 through 15 by longitudinal creases and cut to an over-all length somewhat greater than the over-all length of roll 30 with its support panels 31 and 32. End wall members 17 and 18 are formed of a size and shape that will closely fit over panels 31 and 32, respectively, when the container is in the closed position.

If desired, flaps 20 and 24 can be fastened into position along the ends of bottom wall 11 by staples or other suitable means. End panels 31 and 32 are mounted on a roll of material 30 as described above and the roll can be lowered onto bottom wall 11 with end panels 31 and 32 resting on the interior side of flaps 20 and 24, respectively. End walls 17 and 18 can then be pressed up flush against panels 31 and 32, respectively. Walls 12 and 13 are then brought to a vertical position with flaps 21, 22, 25 and 26 held in position inside the container by walls 12 and 13. Flaps l9 and 23 are depressed downward and wall portions 14 and 15 are placed thereover holding those flaps in position inside the container.

With wall portions 14 and 15 held in a horizontal position defining the top wall of the container, a tubular sleeve of heat-shrinkable plastic film 40 (e.g., a sleeve of polyvinyl chloride film) is slipped around the entire body member 10 of the container as shown in FIG. 3. Other suitable films for making such sleeves are heat-shrinkable films of polyethylene, polypropylene, polyethylene terephthalate, and the like. Holding wall portions 14 and 15 may be accomplished by temporary holding means such as a fugitive adhesive which would adhere the underside of portions 14 and 15 to the top side of flaps 19 and 23 but would cease to function as an adhesive shortly after the container is assembled and thus would not continue to hold the portions 14 and 15 in place. An easily-removed mechanical brace or the like can serve the same function as long as it is removed before the sleeve is shrunk on. Another sleeve of similar heat-shrinkable plastic film 41 is slipped around the container so as to cover the end walls 17 and 18 as shown in FIG. 3. The container walls are loosely held in position at this point. Next, the entire container with sleeves 40 and 41 in position is subjected to an exterior source of heat sufficient to cause the heat-shrinkable plastic film to be shrink-fit tightly around the container as shown in FIG. 4. Suitable means such as heat tunnels are well known in art.

Although sleeves 40 and 41 are depicted as not enveloping the entire surface of the container, that can be done by making sleeve 40 coextensive in width with the length of the container and sleeve 41 coextensive in width with the width of the container. The two sleeves can be heat sealed together, if desired, along the vertical edges of the end walls 17 and 18 to seal the entire container. Moreover, a third sleeve (not shown) can be placed around the container so as to cover end walls 18 and 19 and side walls 12 and 13; after heat shrinking all such sleeves, the container would be sealed at all sides and edges thereof.

FIGS. and 6 illustrate an alternative way of fitting the plastic film around the container. In this embodiment, sleeve 50 corresponds to sleeve 40 in FIG. 3 but is of extended length as shown. Preferably, in this embodiment, sleeve 50 is formed from a biaxially-oriented film so that shrinkage will occur in both directions. When the container with sleeve 50 in position is subjected to an exterior source of heat sufficient to cause the heat-shrinkable plastic film to shrink-fit tightly around the container, the extended length of the sleeve 50 shrinks tightly against end walls 17 and 18. Thus, all edges and openings of the container are covered thereby protecting the contents from exterior contamination.

The material packaged and shipped in the container as described hereinabove is tightly held suspended between end panels 31 and 32 such that any movement of the roll during shipment is effectively prevented. Moreover, damage to the roll surface is greatly inhibited by the distance between the roll surface and the walls of the body member 10. Wrapping the exterior of the container with the plastic material greatly inhibits entry of contaminants through openings, cracks and the like.

One of the greatest advantages provided by this invention, however, is attendant in opening the container. This can be accomplished by slitting the plastic film covering the container. When this is completed, the plastic film portions fall away and the resilience in the creases between the walls of body member and the flaps of end walls 17 and 18 (plus any entrapped air) cause the container to spring open to a position similar to that depicted in FIG. 2 leaving the roll of material 30 suspended between panels 31 and 32 in a free-standing position permitting easy access from all directions without manipulating the material, and thereby decreasing the risk of damaging it. Also, this method of opening does not generate particulate matter which can contaminate the material before it is removed for use.

Another outstanding feature of the invention is that of versatility. By this it is meant that it is no longer necessary to have a wide variety of lengths of containers to accommodate the many different lengths of film rolls produced in a commercial film manufacturing plant. Neither is it required to stuff the ends of a readymade container to prevent jostling movement of a roll significantly shorter than the container. These advantages are realized because a large number of standard size end walls like 17 and 18 with the flaps thereon can be made up to receive standard size panel members such as 31 and 32. No matter how long the roll or how little material is wound on it, a single size panel and end wall can be employed. The only varying factor will be length of the body member 10. However, body members can be readily cut to custom lengths from longer sections. Even in the body members, the widths of walls 11 through 15 will be standardized to go with the standard size panels and the end walls. Eliminating the need for stuffing material to fill void spaces between the roll ends and container ends eliminates a prime source of contamination internal to the container. Shrinkwrap encapsulation provides a barrier to moisture, air-borne particulate contamination, etc. from sources external to the package. The wrap-around concept of applying the container reduces the need for maneuvering the roll in certain axes thereby reducing the probability of damage of roll surfaces, as is inherent with existing endopening containers.

As many widely different embodiments of this invention may be made without departing from the spirit and scope thereof, it is to be understood that this invention is not limited to the specific embodiments thereof except as defined in the appended claims, and all changes which come within the meaning and range of equivalence are intended to be embraced therein.

We claim: 1. In a method of packaging a material sensitive to contaminants, the steps of enclosing opposing ends of said material with a pair of separate end walls each having inwardly directed flaps arranged along its periphery,

enclosing the remainder of the material with an integral body member having a top wall, a bottom wall, and a pair of side walls, which walls substantially cover said top, bottom and sides,

holding the flaps of said end walls in position solely by positioning said flaps inside and in contact with the walls of said body member, and

shrink-fitting a plastic film around said body member and said end walls.

2. The method as defined in claim 1 wherein said shrink-fitting is accomplished by placing a sleeve of heat-shrinkable plastic film around said body member and a sleeve of heat-shrinkable plastic film around said end walls and exposing said films to sufficient heat to cause them to shrink tightly around said body member and end walls.

3. The method as defined in claim 1 wherein one flap on each end wall is fastened to the inside of said bottom wall.

4. In a method of packaging a roll of plastic film wound on a cylindrical core, which film is sensitive to contaminants, the steps of suspending said roll between a pair of end-suspension support panels,

enclosing each of said panels with a closely fitting separate end wall having inwardly directed flaps arranged along its periphery,

enclosing the remainder of the space between said panels with an integral body member having a top wall, a bottom wall, and a pair of side walls, which walls substantially cover said top, bottom and sides,

one flap on each end wall being fastened to the inside of said bottom wall, holding the remaining flaps of said end walls in position solely by positioning said flaps inside and in contact with the walls of said body member, and shrink-fitting a plastic film around said body member on said end walls.

5. The method as defined in claim 4 wherein said shrink-fitting is accomplished by placing a sleeve of heat-shrinkable plastic film around said body member and a sleeve of heat-shrinkable plastic film around said end walls and exposing said films to sufficient heat to cause them to shrink tightly around said body member and end walls.

6. The method as defined in claim 4 wherein one flap on each end wall is fastened to the inside of said bottom wall. 

1. In a method of packaging a material sensitive to contaminants, the steps of enclosing opposing ends of said material with a pair of separate end walls each having inwardly directed flaps arranged along its periphery, enclosing the remainder of the material with an integral body member having a top wall, a bottom wall, and a pair of side walls, which walls substantially cover said top, bottom and sides, holding the flaps of said end walls in position solely by positioning said flaps inside and in contact with the walls of said body member, and shrink-fitting a plastic film around said body member and said end walls.
 2. The method as defined in claim 1 wherein said shrink-fitting is accomplished by placing a sleeve of heat-shrinkable plastic film around said body member and a sleeve of heat-shrinkable plastic film around said end walls and exposing said films to sufficient heat to cause them to shrink tightly around said body member and end walls.
 3. The method as defined in claim 1 wherein one flap on each end wall is fastened to the inside of said bottom wall.
 4. In a method of packaging a roll of plastic film wound on a cylindrical core, which film is sensitive to contaminants, the steps of suspending said roll between a pair of end-suspension support panels, enclosing each of said panels with a closely fitting separate end wall having inwardly directed flaps arranged along its periphery, enclosing the remainder of the space between said panels with an integral body member having a top wall, a bottom wall, and a pair of side walls, which walls substantially cover said top, bottom and sides, one flap on each end wall being fastened to the inside of said bottom wall, holding the remaining flaps of said end walls in position solely by positioning said flaps inside and in contact with the walls of said body member, and shrink-fitting a plastic film around said body member on said end walls.
 5. The method as defined in claim 4 wherein said shrink-fitting is accomplished by placing a sleeve of heat-shrinkable plastic film around said body member and a sleeve of heat-shrinkable plastic film around said end walls and exposing said films to sufficient heat to cause them to shrink tightly around said body member and end walls.
 6. The method as defined in claim 4 wherein one flap on each end wall is fastened to the inside of said bottom wall. 